.card{
    background: #fff;
    box-shadow: 0 2px 2px rgba(0,0,0,0.24),0 0 2px rgba(0,0,0,0.12);
    position: relative;
    top:0;
    
    
    
    transition: box-shadow .3s;
    -moz-transition: box-shadow .3s;  /* Firefox 4 */
    -webkit-transition: box-shadow .3s;   /* Safari 和 Chrome */
    -o-transition: box-shadow .3s;
    
    &:hover{
        box-shadow: 0 8px 8px rgba(0,0,0,0.24),0 0 8px rgba(0,0,0,0.12);
        top: -2px;
    }
}
